Re: Probable Bugs & Suggestions
Fri, 19 Dec 1997 13:36:18 +0100 (MET)

> The calibration would correct effect of a certain scanner printer combination.
> However, it would be a general correction not only valid for a printed and
> then rescanned image, which would indeed make not very much sense, but for any
> image.

No. This would assume the scanner has a gamma of 1.0.

The "Right Thing to Do" (TM) would be :

Get a printed reference color table. These are available from some photo
companies like Kodak.

Now scan this one. As the color values of the table are known, the
response curves for the scanner can now be calculated.

Now you have to compare the values with the monitor image and modify the
response curve until they match (assuming there is only a normal gamma
mismatch, there are simplified tests for that like the 50% value <->
black/100% comparision).

To calibrate the printer, you now print and scan the result. As the scanner
is already calibrated, you can now calculate the printer response.

I.e. you need to calibrate each device individually. otherwise you only get
a combined response which is only valid for the same "image path".


Andreas Beck              |  Email :  <>

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